P1053: NEUTROPHIL-TO-LYMPHOCYTE AND PLATELET-TO-LYMPHOCYTE RATIO AS NOVEL PROGNOSTIC BIOMARKES IN BCR-ABL NEGATIVE MYELOPROLIFERATIVE NEOPLASMS
Authors: Mirjana Cvetkovic, Jelena Ivanović, Isidora Arsenović, Mihailo Smiljanic, Magdalena Karasek, Olga Chyrko, Andrija Bogdanovic, Marta Sobas, Danijela Lekovic
Journal: HemaSphere (2023)

Topic: 16. Myeloproliferative neoplasms - Clinical Background: Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) recently emerged as biomarkers reflecting inflammation, atherosclerosis, cell activation. Studies have shown that a higher NLR and PLR have been associated with increased risk of thrombosis, cardiovascular mortality in general population, but their roles in myeloproliferative neoplasms (MPN) remain unclear. Aims: Aim of our study was to analyze NLR and PLR as prognostic markers for thrombosis and overall survival (OS) in MPN patients. Methods: A retrospective study included 461 consecutive patients with MPN diagnosed according to WHO 2016 classification and treated between 2018-2022 at University Clinical Center Serbia. Twenty age-matched patients without hematological disorder were used as controls. Results: Previous thrombosis was present in 23% of patients, concomitant diagnosis of thrombosis and MPN was observed in 1.5%, while 6.9% pts were diagnosed with thrombosis during follow-up. Incidence of thrombosis before and during follow-up was highest in PV>PMF>ET. NLR and PLR were significantly increased in whole MPN group compared to controls (Table). NLR was the highest in PV followed by PMF and ET (p<0.001). On the contrary, PLR values were the highest in ET, then in PMF and the lowest in PV (p<0.001). Correlation between NLR and PLR was found in all cases. Older age (p<0.001), male gender (p=0.037), higher leukocytes (p=0.012) and higher LDH (p=0.002) correlated with higher NLR, while lower hemoglobin (p<0.001), higher leukocytes (p=0.004) and platelet count (p<0.001) correlated with higher PLR. Similar incidence of arterial and venous thrombosis was found during follow-up (3.3% and 3.6% respectively). Thrombosis occurrence during follow-up correlated with NLR (p<0.001), NLR≥4.5 (p<0.001), PLR (p=0.008), presence of at least two CV risk factors (p=0.03) and previous thrombosis (p<0.001). Arterial thrombosis was associated with previous thrombosis (p=0.043), NLR (p=0.003), NLR ≥4.5 (p=0.004). Similarly in venous thrombosis pts, history of thrombosis was risk factor (p<0.001), together with NLR (p=0.003), NLR≥4.5 (p=0.017), PLR (p=0.029), but also secondary malignancy (p=0.045) and female gender (p=0.034). No association with age, baseline leukocytes, hemoglobin level, platelet count, spleen size and presence of JAK2V617F mutation were found. In multivariate Cox regression model (table) most important factors for development of thrombosis during follow up were previous thrombosis, NLR≥4.5 and PLR≥500. For arterial thrombosis similar factors have impact, NLR≥4.5 and previous thrombosis; for venous thrombosis PLR≥500 and previous thrombosis. Patients with pre-PMF had significantly higher NLR then patients with ET (table) and NLR≥4.5 was significantly associated with profibrotic PMF (p<0.001). During the median follow-up of 33 months (1-110), 55 pts (11.9%) died. Unfavorable prognostic factors for OS were age ≥60y (p=0.01), PMF (p<0.001), presence of second malignancy (p=0.04), NLR≥4.5 (p<0.001), PLR≥500 (p<0.001), presence at least three CV risk factors (p=0.042). In multivariate Cox regression model the most important factors associated with survival were NLR≥4.5 and PLR≥500 (table). Summary/Conclusion: This study highlights strong prognostic correlation of NLR≥4.5 and PLR≥500 with development of thrombosis and OS in MPN. Besides previous thrombosis, most important factor associated with development of arterial thrombosis is NLR≥4.5, but PLR≥500 for venous. Our results revealed that NLR≥4.5 could be used as additional marker to distinguish ET from profibrotic PMF.Keywords: Myeloproliferative disorder, Survival, Thrombosis